UKIP has lost its only MP after Douglas Carswell resigned declaring "job done".

His resignation was met with suggestions by senior Ukip figures that he was actively working to undermine the party and that he quit before being kicked out.

But the Clacton MP, who insisted he does not have to call a by-election because he will sit as an independent rather than joining another party, denied that he was involved in "subterfuge".

Amid claims that he only defected from the Tories as part of a plot to marginalise Nigel Farage's role in the EU referendum, Carswell admitted he wanted the Brexit campaign to be more "positive", apparently referring to the former leader's controversial views on immigration.

Carswell said: "The idea that I was involved in sort of subterfuge or some sort of covert operation is nonsense."

He added: "I spent the referendum campaign arguing that the people running the campaign should be positive and broad-minded.

"I don't think any of this is something that I've kept secret, and it's no secret either that some in Ukip wanted to make sure that Ukip ran the referendum campaign.

"I've been pretty open about the fact that Eurosceptism to be a force for change needs to be inclusive, upbeat, progressive and forward-looking."

Carswell also revealed he had not spoken to Farage since around December and urged him to be more positive "about the fact that on Wednesday, we win" – referring to the Prime Minister's intention to invoke Article 50 to begin the UK's withdrawal from the EU.